Anserine (N-β-alanyl-1-methyl-L-histidine) or carnosine (β-ananyl-L-histidine) in which β-alanine is bonded to histidine or methylhistidine, respectively is a histidine derivative abundantly available in muscles of mammals, birds, reptiles, amphibian, etc. and has been reported to have various pharmacological actions.
For example, it has been disclosed that anserine has an immunomodulating action (refer to Patent Document 1) and an anti-stress action (refer to Patent Document 2) and that anserine and carnosine have a suppressive action for hypertension (refer to Patent Document 3), a promoting action for iron absorption (refer to Patent Document 4), an enhancing action for learning ability (refer to Patent Document 5), a promoting action for zinc absorption (refer to Patent Document 6) and antioxidant/anti-aging/anti-cancer actions (refer to Patent Document 7). However, there has been no report for their analgesic action.    Patent Document 1: Japanese Examined Patent Publication No. Hei-06/041,411    Patent Document 2: Japanese Patent Laid-Open No. Hei-09/020,660    Patent Document 3: Japanese Patent No. 2,939,301    Patent Document 4: Japanese Patent Laid-Open No. Hei-07/097,323    Patent Document 5: Japanese Patent Laid-Open No. Hei-09/020,661    Patent Document 6: International Publication WO 01/091,762    Patent Document 7: Japanese Patent Laid-Open No. 2003/267,992